Organic Gemstone (Not A Rock Or Mineral)

Sunstone

Oligoclase or Andesine (Labradorite) Feldspar (Na,Ca)(Si,Al)4O8

Turquoise

Hydrated copper and aluminum phosphate (CuAl6(PO4)4(OH)8·4H2O)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Nuummite

Nuummite (Orthorhombic amphiboles: Anthophyllite and Gedrite)

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

Unakite

Unakite (Metasomatized Granite)

Fossiliferous Rock (likely Dinosaur Fossil in Matrix)

Permineralized Vertebrate Fossil (Calcium Carbonate/Silica replaced bone material)

Quartzite with Quartz Vein

Metamorphosed Quartz-rich Arenite (SiO2)

Blue Sapphire

Corundum (Al2O3) with traces of Iron and Titanium

Yellow Agate

Chalcedony (cryptocrystalline silica), SiO2

Blue Tiger's Eye

Crocidolite in Quartz (altered)

Mineral

Chert (specifically Flint)

Silicon Dioxide (SiO2)

Chert (often called Jasper or River Siltstone)

Microcrystalline Quartz (SiO2)

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)

Quartz (Milky or Clear variety)

Silicon Dioxide (SiO2)

Fossiliferous Limestone with Rugose Coral

Calcite (CaCO3) matrix containing Rugosa (order of extinct solitary and colonial corals)

Moldavite

Tektite (Impact Glass), ~80% SiO2 + Al2O3

tektite

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Turquoise

Turquoise (Hydrated phosphate of copper and aluminium) CuAl6(PO4)4(OH)8·4H2O

Turquoise

Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)

Blue Sapphire

Corundum (Al2O3)

Jasper (Red Jasper)

Silicon Dioxide (SiO₂)

Chert (Jasper variety)

Silicon Dioxide (SiO2) with iron oxide impurities

Chert / Flint

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Chert (Nodule)

Microcrystalline Quartz (SiO2)

Ironstone concretion / Limonitic Sandstone

Goethite/Hematite Cemented Sandstone (Hydrated Iron Oxide)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Clear Quartz (Carved Dragon)

Quartz (Silicon Dioxide, SiO2)

Amber

Succinite (C10H16O)

Chert (Jasper/Quartzite variety)

Microcrystalline Silica (SiO2)

Chert (Flint nodule)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Citrine Geode Fragment

Citrine (Silicon Dioxide with Iron Impurities), SiO2

Charoite

Charoite (Hydrated potassium sodium calcium barium strontium silicate hydroxyfluoride)

Green Moonstone (Garnierite)

Nickel-bearing Magnesium Silicate (often a mix of Serpentine and Talc/Chlorite groups)

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

Pyrite

Pyrite (Iron sulfide, FeS₂)

Mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Quartz (Milky or Clear Quartz fragment)

Silicon Dioxide (SiO2)

Amethyst

Amethyst (Silicon Dioxide with Iron impurities, SiO2)